Relative to the kill operation this will make it more complex but it can be done. They will have to kill the outside flow around the casing. If the 9-5/8 is still intact down hole the well will then be dead. If it is not intact they will then need to do a second kill operation to stop the flow that would be coming into the 9-5/8.
The kill wells will be drilled into the oil pay zone. They will then breakdown the formation by pumping seawater down hole under many thousands of pounds of pressure. Once good communication is established they will follow with kill mud and then a huge cement job. This will have to be done once if the 9-5/8 is intact. Otherwise it will be done twice, once on the outside and once on the inside.
If the oil is reaching the surface around the backside of the casing, wouldn’t that indicate a significant casing breach at the lowest levels? The flow path of the product has been eroding and flushing huge amounts of sedimentary soils up to the ocean bottom. Is there enough mud on the planet to effectively fill this void and choke off the flow? I appreciate your hard-earned insights on this grave matter.